Ghost of Vengance
by HarryPotter4Ever-celia
Summary: Erin Gilbert thought she'd seen it all, but that was before she found out about wizards, benevolent ghosts, and a plan to destroy the wizard world. And she definitely didn't bank on falling in love. Characters listed are not the only important ones! Rated K just in case.
1. Thoughts at Night

_**Hey guys. So I decided to try something new with one of the best movies of 2016,**_ **Ghostbusters!** _**And also Harry Potter, obviously. I'm not giving any spoilers, but I hope you'll enjoy it. Expect this to be short, but not too short.**_

* * *

 ****

 **Harry woke up, clutching his scar. It was close to two in the morning, and his scar hadn't hurt like that for a good twenty years.**

He rolled over in his bed to look at Ginny, forgetting that he was at the Burrow for Christmas. For old time's sake, he stayed in Ron's bedroom with him and Neville whenever he was at the Burrow. Ginny was in with Hermione and Luna, and the kids were in the living room. Angelina, Fleur, Hannah Abbott and Audrey stayed together, and so did Bill, Charlie, George, and Percy. The house was small, but they made it work. And, whenever any of the kids, especially Harry and Ginny, offered to host, Molly was adamant.

"Christmas at the Burrow is a family tradition!" She would insist. "And this is our home. A _family_ home." So every year, like clockwork, here they were.

Harry stared out in the darkness. What would they all say? His scar hadn't hurt since Voldemort died. No, it was probably just sinuses….or a phantom dream….or….

What was it that Teddy Lupin had said, though? There was a nagging feeling that something was off, that something hadn't been right for a good number of years. "The ghosts are very agitated," his godson had told him over the summer. "Write to James and Albus often to make sure everything is okay. I have a feeling I'm going to be needed this year, as Head Boy."

Harry had dismissed it, but now, his scar was burning. He rolled over and tried to go back to sleep, knowing he would have to hold a meeting in the morning.

* * *

In New York, Erin Gilbert was wide awake. She just couldn't sleep, even though she was in the firehouse of her friends' dreams. Things had been just a little _too_ quiet after the portal closed. Sure, Holtzman was still designing, Abby was still in charge, Patty was still her nervous self, and Kevin was still….well, Kevin. But things were much too slow, and she couldn't help feeling that something was looming on the horizon.

* * *

 _ **So, I hope this isn't terrible. Please let me know what you think, this is the first Harry Potter Ghostbusters fic for the new movie (with a primarily female cast, if you haven't seen it I highly recommend it). I hope it can work.**_


	2. Slime and Scars

_**Just so you know, I have no idea what I'm doing. But Merry Christmas to all those who celebrate! Happy Hanukkah day 2 for all those who celebrate! Happy Kwanzaa (tomorrow) for all who celebrate. Happy whatever to anyone who has ever celebrated anything in December!**_

* * *

After thinking long and hard, Harry decided he would tell only two people immediately. Hermione and Luna would know what to do, everyone else could wait until after the holidays. It was Christmas Eve, after all, and he certainly didn't want to spoil anyone's Christmas. He fell back into a fitful sleep.

* * *

Erin had put her worries aside for Christmas. The mood that Holtzman set changed everything, and she couldn't help but burst out in joyous laughter when she and Abby pulled the Christmas cracker that had two white-haired dolls climbing out of a hole, obviously handmade.

Abby tried to glare at Holtzman, but the latter just said, "You love me," and enveloped Abby in a bone-crushing hug. Patty stood on the sidelines, laughing and rolling her eyes. Erin hadn't felt so at home in years.

Kevin had finally brought Mike Hat to meet them. Mike Hat, as it turned out, was a fancy poodle with a very French cut. _Leave it to Kevin to have a dog like that_ , Erin had thought when she first saw their receptionist's furry friend.

Kevin had already won the dance battle that he put them all up to, although Patty was a close second. He'd called (having finally figured out how to use the phone) the same sub shop where he'd got his sandwich during the apocalypse, which for some reason was bending to his every will. It was totally euphoric, and Erin had completely forgotten her looming dread.

"Time for presents," Abby called after she finally pulled Holtzman off her. "I'll give mine first."

They all turned their attention to the beautiful, slightly scary tree that Holtzman had put up. It had ghost ornaments and strange machines everywhere.

Abby gathered up her packages. "I made snow globes for all of you," she said excitedly. "This one here's for Kevin."

Kevin grinned his goofy grin, and took the box out of Abby's hands. He tore open the paper. "It's a fish….on the phone?" His expression changed from joyous to very confused.

"Remember your first day on the job?" Abby was smirking. "When the phone rang, and you said you couldn't answer it because it was in the fish tank?"

Patty, the only one who hadn't been there during Kevin's first call, roared with laughter. Erin and Holtzman just chuckled. Kevin was flummoxed.

"Here's Patty's," Abby giggled once the laughter had died down. Patty gave the package a skeptical glance before lightly tearing the paper.

"Is that….me crowdsurfing with a demon on my back?" Patty laughed incredulously. "Wow, Abby. Just wow."

Erin had forgotten Abby's funniest moments, but now, everything came back to her clearly. She suddenly remembered the pranks that Abby would play on anyone who dared to call Erin a liar about her paranormal experience.

"You know I never actually crowdsurfed, right," Patty scolded. "They all dropped me before I could."

Abby rolled her eyes, handing Holtzman hers. Grinning, Holtzman tore the paper with great enthusiasm.

"It's me building!" She said excitedly.

"And last, but certainly not least, Erin."

Erin wondered if she really wanted to know what was inside that box. Tentatively, she took the gift from Abby.

"Go ahead, it won't _bite_." The way Abby said that made Erin wonder what exactly it _would_ do.

"Oh no. There's no way…." The little orb depicted Erin getting slimed from all directions. "Very funny." She tried to sound unimpressed.

"Wait, press this button!" Abby said excitedly, and Erin shrugged. How bad could it be? She reached out for the button, and slime sprayed everywhere.

"Abby Yates, I am going to kill you!" Erin screamed, now covered in slime.

Everyone else roared with laughter.

* * *

Back at the Burrow, where gifts had been opened and the secret Santa between the kids had been completed, Harry was waiting for a good time to catch Hermione and Luna alone when Teddy came up to him.

"What's going on, Harry? You've been down all day."

"Teddy…." Harry didn't know if he really wanted to tell his godson, but he decided he'd almost have to.

"What was it you said at the beginning of the year? About you being needed as Head Boy?"

Teddy looked worried. "I said that the ghosts have been really anxious. Even Peeves. I think something is coming, but I couldn't say what."

Harry nodded.

"You look sick, Harry."

Harry suddenly clutched his forehead, which could have been splitting open for all he knew. Teddy screamed, and the whole world went black.

* * *

When Harry came to, he was lying on the couch, surrounded by his friends. He looked around at everyone, and then realized what had happened.

"He's back, and he's at Hogwarts."

* * *

 _ **A/N: Well, here's my second chapter. Don't worry, things will pick up quite a bit more now that Harry's realized what's going on. Soon, Erin Gilbert will learn what was bothering her. And I bet you can guess who the Ghost of Vengance is, can you not? *Laughs evilly.***_

 ** _~Hufflepufferfish_**


	3. Curious Meetings

After driving his kids to King's Cross station, Harry parked the car. "If you see us in Hogsmeade, don't worry," he told the kids. "We've just got some business to take care of, routine auror stuff, nothing special. If you need anything, find Teddy or Neville. We'll let you know if we'll be at the school. Good luck!"

"And Albus dear," Ginny called, "don't forget to thank Scorpius for that batch of Quidditch muffins he sent you, those must have taken forever!"

James rolled his eyes, but Harry suspected he was just jealous because his friends hadn't sent him anything half as cool.

Hermione and Ron met up with Harry and Ginny. Luna and Draco waved as they sent their kids on the bus, and then walked over to the four of them.

"Where should we meet up?" Draco asked, not quite meeting Harry's eye. Despite their sons being close friends, Harry and Draco were still on uneasy terms. But Hermione had convinced him that he had to be part of the solution to whatever the problem was.

"Let's go to the Hog's Head, Aberforth is always willing to give us a room," suggested Ron.

Everyone nodded, turned, and apparated on the spot.

* * *

Erin woke up with the strange feeling of needing to go to the United Kingdom right away. It was strange, especially since she had never been there. But to convince the girls to take a trip, well, that would be another matter.

Patty knocked on the door to her room. Erin had been the fastest to learn each of her friend's knocks and breathing patterns, because she was a jumpy person and didn't want Holtzman to sneak up on her at any point.

"What's up?" Erin asked, opening her door. She was still in her pink pajamas, but it was Saturday, and unless there was anything pressing, they always hung out in pajamas and binge-watched Netflix until whenever on the weekends.

"So, I was thinking, we should plan a girls day soon. You know, just the four of us. Maybe we should hop on a plane and travel somewhere, get away from New York City, you know?"

"I'd love to. Where to?"

"I was thinking maybe a tour of the British Isles. I've heard they're really beautiful this time of year, with the snow and everything."

"That's perfect. Have you told the others?"

"Not yet. But I already have the tickets and everything. We leave in two days."

"That's my birthday! January 21st."

Patty grinned. "I know. Abby told me. We've been planning this for months."

"But didn't you just say…."

"I know what I just said. I lied, girl. We wanted to give you something special. So get packing!"

"What about Kevin?"

"We bought him a new phone. I think he'll be okay."

Erin couldn't help but laugh.

* * *

Holtzman had insisted on packing all of their equipment. "You'll never know when we might need it," she declared. But getting it all through security was another matter.

"Sir, we're the Ghostbusters," she pleaded with the guard. "You must've heard of us, we stopped a ghost invasion in New York last summer!"

"I need proof," the officer insisted. "Do you have a license? An official website?"

"Um, we have a logo," Erin said quickly, turning to show him her backpack.

"This looks like it was painted on a subway wall and then transcribed onto some merch," the man scoffed.

Abby already had her phone out. Erin knew instinctively that she was calling Jennifer Lynch at the mayor's office. They were willing to fully fund anything the Ghostbusters did, and they would definitely vouch for the crew and their guns. Within a few minutes, the group had their bags checked and they were ready to go.

* * *

"Seven hours," Holtzman sighed, reclining her seat into Patty's lap.

"Hey!" Patty looked at Erin, who pulled out a water gun.

"Are you kidding me?" Abbey asked, exasperated, but it didn't appear that she was talking about whatever her immature friends were doing now. She had her face buried in the in-flight magazine. "Benny's a 'critically acclaimed Chinese cuisine chef' now. He wrote this himself, look at it. Where's the flight attendant, I need to buy wifi."

Erin rolled her eyes and, squirted Holtzman a few times for good measure. Then, she popped in her headphones and let Rachel Platten fill her ears.

* * *

"So, what's the plan?" Draco asked, clearly dumbfounded.

"I wish we had one," Hermione said, looking grim. "I don't think anyone suspected he would reappear as a _ghost_."

"If you must be dead, then I guess you have to return undead," Ron muttered. Everyone nodded in shocked silence.

"But wait, hold on, how much power can he actually _hold_ as a ghost? I mean, it's not like he can use a wand, right?" Draco was still skeptical.

Harry looked uncomfortable. "I doubt that's his, er, final form. Think, Draco. What are three things we know could return him to his former body and make him the master of death?"

"Oh, no. You can't possibly believe-"

"He'd have to get through us to get the invisibility cloak, and the resurrection stone was lost in the forest. However, the wand is not a problem for him. He's already been in Dumbledore's grave once in life, so why wouldn't he attempt to go there in death as well?"

"If you're quite sure," Draco scoffed, "get McGonagall to ban all copies of _Beedle the Bard_ in the school. She _does_ know, doesn't she?"

"I told Teddy to drop her a line. I hope to arrange a conference with her. He's doing a great job of laying low, though. It will be hard to get her to understand. What we need is Helena Ravenclaw."

Everyone glanced over at Luna. "No way," Luna said firmly. "I'm _not_ getting her involved in this. She still mistrusts me after, well, you know. I can't put her through this."

"The Bloody Baron does his fair share of skulking, too." Draco pointed out. "He'll listen to me, and to you if I say you're with me."

"I want just the two of us to go, then. We can leave tomorrow, but I need some time to piece things together."

"Potter, I just wanted to say…."

"Me too. It's in the past. We're on the same side now. And about Voldemort…."

The word hung in the air for a second. During the conversation, the name had yet to come up, although everyone knew who "he" was."

"Draco," Ron finished for Harry, "it's not your fault."

* * *

Ever since Astoria had decided she didn't want to be involved after Scorpius had been born, Draco had been spending some time at Muggle bars and restaurants. It had nothing to do with meeting people; he just wanted to be less ignorant. He knew he had been a jerk in the past to Muggles and Muggle-borns, but he wanted to make up for it. He didn't want Scorpius to have the same childhood as him, and he knew that that meant he'd have to be different than his own parents had been.

Draco found himself at Uncle Tao's in Chinatown that night. He hadn't been to a Chinese place in ages, and he was really craving some good noodles. He usually sat alone, and that night was no exception.

For the most part, the restaurants Draco went to were never _too_ crowded. He sometimes liked to watch customers, especially people who were obviously foreigners. And the four young women across from him were definitely not local. They carried bulging backpacks with weird tubes sticking out. The blonde one had a t-shirt with something Draco could only assume was a Muggle impression of a ghost. Could Muggles see ghosts, for real? Draco wouldn't be surprised if they could.

The four women didn't seem to be related, but probably close friends. They were constantly teasing each other, and every so often, Draco saw one of them take out a water gun and threaten the others.

"See, this is actual wonton soup!" The brunette with glasses exclaimed.

"Abby, you do know that that place is your basic fast food and delivery," the tall, African American one scolded. " _And_ we live in New York City. It's not like you _couldn't_ get actual Chinese food if you wanted."

"Ah, but there's _Benny_ ," the blonde one said exaggeratedly, rolling her eyes.

The fourth one, who had stayed quiet, pulled out her water gun again. "Holtzman! Stop saying that! You _know_ she doesn't like him like that!"

"Or at all," the one called Abby muttered.

Draco smiled from his table two spots away. Muggles weren't really that different from Wizards. He got up to use the bathroom.

* * *

Of course it had been Abby's idea to stop at the first _real_ Chinese place they saw once they got to London. They hadn't even been to the hotel yet, but everyone was hungry. Erin hadn't wanted to, but she was outnumbered. _Whatever_. She slept on the plane, and she had done much worse.

Dinner was surprisingly enjoyable despite everyone being tired and jetlagged. They still managed their usual ways and conversational style.

Erin had noticed a blond man glancing at their table a couple of times. He had startling blue eyes. She saw him walk into a corner, and she figured that must be where the bathroom was. She realized she'd had a bit too much lemonade herself.

"I'll be right back."

The others nodded and went back to teasing Abby about Benny. Erin rolled her eyes.

She was disappointed to see that there was a line for the bathroom. There were about eight people in front of her.

"Is it a single room?" She asked the person in front of her.

He turned around. It was the blond guy from earlier. "Yeah, unfortunately. It's usually not this busy."

"Is this your favorite place?" Erin asked. Might as well talk to pass the time.

"I come here often, yeah. There's a lot of good places in Mu-in London." Draco had almost slipped up and said Muggle London.

She nodded absently. What had he been about to say? It didn't matter. "That's good to know. Any recommendations?"

"Well there's this place….actually, no, it's not that good. But I think it will be easy for you and your friends to find something." Mentally, he was kicking himself. Two slip-ups in one conversation? That was harsh, even for him. Not that he had that many conversations with Muggles, but still.

* * *

"Who was he?" Patty demanded in the hotel room.

"Who?" Erin was genuinely confused.

"The guy who was watching us. Come on, Erin, I'm not dumb, I saw you follow him."

"Oh, I was just going to the bathroom. He's just some local guy, I guess."

"You spent a long time there."

"It was single stall, there was a line."

"So he was there too." It wasn't a question.

"Yeah. I asked him for restaurant recommendations, but he didn't really know any. He was kind of weird about it, as if he wasn't supposed to be there."

"Strange."

"Did Abby or Holtzman notice he was watching us?"

"I don't think so, they didn't say anything if they did."

Erin breathed a sigh of relief. "Good. You know how Abby gets about people watching us, even back home."

It was true. Abby hated being famous.

* * *

As Draco sprawled across the bed in his two room apartment that night, he thought about how he hadn't even gotten the girl's name. She had been very pretty, but Draco didn't really expect to see her again. After all, London was a big city, and he was a wizard while she was a Muggle. _And_ they had the threat of Voldemort's ghost to worry about.

* * *

 _ **A/N: So I changed my name but it's still me I guess. I'm going to the Dominican Republic on Sunday, and I'll be there for three weeks without much internet access, so I'm trying to get chapters out in a lot of my stories, even if they're short/filler.**_

 _ **I also don't really know where I'm going with this. I know it has something to do with the Hallows, as well as the crossover/romance stuff, but that's about it.**_

 _ **If you're reading this, please review or at least say hi. Thanks**_

 _ **~ .5thWaver (formerly Hufflepufferfish)**_


	4. Little Talks

Harry woke up dreading the day. He hadn't really wanted to talk to the Bloody Baron, but what other choice did he have?

Draco met him at King's Cross. They figured meeting in a Muggle spot would diffuse any problems that could come up, in case Voldemort was somehow tracking them.

There weren't that many Muggles around, aside from the guards. Harry had a feeling some of them knew about the hidden platform there, and that possibly there were squibs or Muggle parents working there occasionally, especially on Hogwarts days. Nobody ever seemed to question the strange assortment of creatures students carried on those days. Sometimes, they would even make friendly conversation with the students and other wizards.

* * *

After a good night's rest, the group decided to do a bit of sightseeing. It was Patty who got them up early, saying they had to make the best of Erin's birthday vacation. Holtzman and Abby, as always, had insisted on everyone bringing their gear. Erin, however, hadn't liked the idea of bringing it on the underground. But whatever Holtzman wanted in terms of the gear, the others did.

Of course, then there was the issue of currency. None of them had ever seen British pounds before. They would have liked to think they knew what they were doing, but they all failed horribly.

"We should just rent a car," Abby complained. "You used to work in a subway, Patty, you should know how this works!"

Erin was trying to ignore them and actually figure out the money, but she had the strange feeling she was being watched.

"You look lost." Erin jumped.

"Harry, what did you even expect to achieve by saying that? Don't scare the poor girl, she'll think we're some creepy bums who hang out at the underground. Sorry, ma'am."

"Can you show us how to use this?" Erin muttered embarrassedly. "We're…." she trailed off, realizing the young man who had scolded his friend was the same guy from the previous night at the restaurant."

"American?" The man flashed her a dazzling and sincere smile.

"How did you know?" Erin stammered.

"I overheard the four of you last night. Sorry."

The black-haired boy was looking suspiciously from Erin to his friend. "What's this about?" He mouthed. The Chinese restaurant boy just shook his head. Not for the first time, she wondered who they were, and whether everyone around here was speaking in tongues.

Patty came up behind Erin and gasped. "I saw you last night."

Abby and Holtzman were still trying to figure out the money, but they stopped when they heard Patty. Erin rolled her eyes.

"We can help you," the Chinese restaurant boy said quickly. I wondered if he thought this was as awkward as I did. He quickly explained the money, his friend nodding and saying nothing.

Erin and her friends thanked them. "No problem," said the Chinese diner man with a shrug. "I'm Draco, by the way. Draco Malfoy."

What an interesting name. "I'm Erin. Uh….thanks. See you around, I guess."

"Er, yeah," Draco muttered.

* * *

"Since when do you help Muggle foreigners?" Harry said once he was sure the girls were out of earshot. "I'm impressed, Malfoy. You really _have_ changed."

"If you mention this to anyone, Potter, I'll have to obliviate them and kill you. My father especially _cannot_ hear about this."

"I'm impressed," Harry said again. "Where are we meeting the Baron, again?"

"The edge of the forest, near the lake. Come on."

* * *

The Bloody Baron stared, and Harry felt a strange sense, like a hole through his body. He had never been the subject of a ghost's stare before, especially from someone as icy as the Baron. But Draco seemed to be used to it.

"So, Harry Potter. You are sure that He Who Must Not Be Named is back, in the same form as us at Hogwarts?"

"I can't be positive," Harry muttered. "But I had a dream…." He launched into an explanation about what had happened that night at the Burrow.

"I shall alert the other spirits, Mister Potter, but your story has many flaws. The ghosts have been around forever, and to us, He Who Must Not Be Named is merely a blip on the horizon. For now, you must go."

"Go?"

"Go, and heed this: if you live a hundred thousand years, as I have, you will never stop being haunted by him. I've never stopped thinking about Helena, or about what happened after. His ghost, Mister Potter, will always haunt you, whether real or fake."

Harry and Draco exchanged a look. "Baron," Draco pleaded. "Teddy Lupin, the Head Boy from Hufflepuff, he says the ghosts have been agitated recently."

"It is not your concern." The Baron started to fade away into the forest. Harry and Draco had agreed not to bring up the Hallows, but now Draco thought it might make a difference.

"Will you alert the centaurs as well? They'll need to be on the lookout for….for anything suspicious in the forest. Any….strange rocks."

"Draco Malfoy, there is nothing strange about these woods. Students are kept out of it, and unlike in your day, Minerva actually enforces those rules now. Nothing could get in or out without her wanting it too. The centaurs have enough to worry about besides, anyway."

"The centaurs?" Draco asked. He suspected the Baron had dropped an important message without necessarily meaning to. "Something in their stargazing?"

"I cannot tell you that information, Malfoy. Forget I said anything." Then, the Baron faded away before Harry or Draco could ask any more questions.

Draco looked at Harry, wide-eyed. "If McGonagall's truly blocked off the forest, then there must be something really wrong. Technically, it's not even our property. We've got to get in there, Potter."

"What, to talk to the centaurs?"

"Something doesn't add up. It's clear that McGonagall thinks there's someone or some _thing_ in there that shouldn't be."

"You think _he's_ there?"

"Not him, but….some presence that shouldn't be."

Harry nodded, saying nothing. It was all a little too much to process.

* * *

They apparated back to their respective homes, and Draco was shocked by what he saw. "Erin?" The four girls were walking across the street from his apartment. "You're staying _there_?" What were the chances that they would be staying at the hotel on his block?

Erin's eyes narrowed. "Draco Malfoy. Are you stalking me?" She yelled across the street. Abby elbowed her.

"You don't just yell that," Holtzman hissed at her. "Anyone could hear. You have to saunter up to him. Like this."

Before Erin could stop Holtzman, she was across the street. "Hey, Dragon Money or whatever your name is. My friend _Erin_ here doesn't like how you're always around. Why do you run into us so much?"

"Fate?" He mumbled. "Look, I know just as much as you."

The other girls crossed over. "Excuse Holtzman," Erin said. "She doesn't like people, especially men. You really live in one of these apartments?"

Draco indicated his building. "Hey, you ladies seemed lost this morning. Everything work out okay?"

"We didn't get to much, just some ice cream shops and things."

Draco was feeling way too confident. "Want me to show you four around tomorrow?" There were small wizard places everywhere, and a lot of good, independent stores, run by both wizards and muggles. They could also do some of the bigger things London has to offer, if the girls had enough money.

"That would actually be really great," Abby muttered, not looking at Draco. "I'm Abby, by the way. This is Holtzman-" she gestured to the blonde girl with crazy green streaks in her hair- "and this is Patty-." She indicated the taller African American woman who looked slightly older than the rest. "It appears you've already met Erin. We're from New York city, and yes, we've become a little lost. Thank you for your offer"

"My pleasure," Draco said, his gaze drifting from one girl to the next. "Tomorrow morning at, say, ten?"

"Thank you," Erin whispered.

* * *

 _ **A/N: Well, I think maybe I'm making Draco too out of character. Any thoughts on how I can make this better? He's too nice and not Slytherin-y enough.**_

 _ **Also, am I spending too much time with Draco and Erin right now and not enough on the actual story? Please let me know if you feel this way.**_

 _ **Please review! Thank you!**_

 _ **~Celia**_


End file.
